1. Field of the Invention
The present invention relates generally to wheeled, hand-operated vehicles and, more particularly, to hand trucks.
2. Description of the Prior Art
To move boxes and bulky packages that are too heavy and/or bulky to carry by hand, hand trucks are often employed. An exemplary hand truck is disclosed in U.S. Pat. No. 4,776,603. Generally, a hand truck has two wheels, a horizontally oriented platform, a vertically oriented frame assembly extending upward from the platform, and a hand-grip assembly supported by the frame assembly. The frame assembly generally includes vertically oriented peripheral frame members and transverse members connected between the peripheral members.
To move objects with a hand truck, the hand truck must first be loaded. The hand truck and objects are moved, and then the hand truck is unloaded. The load-move-unload cycle must be repeated each time the hand truck is used. There are instances, however, when one may wish to slide an object along a floor, or other horizontal surface, from one location to another without going through the load-move-unload cycle. In this respect, it would be desirable if a hand truck could be adapted for sliding objects along a horizontal surface.
Throughout the years, a number of innovations have been developed relating to hand trucks or other dollies designed to move objects from one location to another, and the following U.S. Pat. Nos. are representative of some of those innovations: 3,476,199; 4,217,967; 4,726,602; and 5,158,032. More specifically, U.S. Pat. No. 3,476,199 discloses a dolly for burial vaults. With this device, a motor and transmission assembly control the movement of the burial vault. To avoid the weight, expense, and overall complexities, it would be desirable if a hand truck were provided that enables rolling an object along the body of the hand truck without the use of a motor and transmission assembly.
U.S. Pat. No. 4,217,967 discloses a roller device that is motorized and provides a seat for an operator. A hand truck generally does not need a seat, and it would be desirable if a hand truck were provided that permits objects to be rolled along the body of the hand truck without having a seat for an operator.
U.S. Pat. No. 4,726,602 discloses a conventional hand truck that has an add-on framework to enable the hand truck to handle bulky freight. The add-on framework does not permit objects to be rolled along the body of the hand truck.
U.S. Pat. No. 5,158,032 discloses a dock dolly that does not permit an object from being rolled along the body of the dolly.
Still other features would be desirable in a hand truck apparatus. For example, in a hand truck that can be used for rolling objects along the body of the hand truck, it would be desirable if the path of object rolling can be extended beyond the length of the frame of the hand truck. In this respect, it would be desirable if an extension assembly for extending the path of rolling could be carried by the hand truck so that the extension is readily available for use. It may also be desirable if an extension assembly for the path of rolling objects along the body of the hand truck be attached to the hand truck in a folding manner.
When a hand truck is used for rolling objects along the body of the hand truck, it would be desirable if means were provided for maintaining the body of the hand truck in a horizontal orientation.
When the body of the hand truck is used as a platform for rolling objects, the horizontal platform of the hand truck may get in the way. In this respect, it would be desirable if a hand truck were provided in which the horizontal platform were easily removed and replaced.
Thus, while the foregoing body of prior art indicates it to be well known to use hand trucks and other wheeled devices for moving objects, the prior art described above does not teach or suggest a hand truck apparatus which has the following combination of desirable features: (1) can be adapted for sliding objects along a horizontal surface; (2) enables rolling an object along the body of the hand truck without the use of a motor and transmission assembly; (3) permits objects to be rolled along the body of the hand truck without having a seat for an operator; (4) permits extension of the path for rolling an object to be extended beyond the length of the frame of the hand truck; (5) carries an extension assembly for extending the path of rolling on the hand truck so that the extension assembly is readily available for use; (6) provides means for maintaining the body of the hand truck in a horizontal orientation when used for rolling objects along the body of the hand truck; (7) provides an extension assembly for the path of rolling objects along the body of the hand truck to be attached to the hand truck in a folding manner; and (8) provides that the horizontal platform can be easily removed and replaced. The foregoing desired characteristics are provided by the unique hand truck apparatus of the present invention as will be made apparent from the following description thereof. Other advantages of the present invention over the prior art also will be rendered evident.